Pick out the correct statement(s) : — d and f Block Elements Chemistry Question

💡 Solution & Explanation

(a) MnO2 + 4HCl $\rightarrow$ MnCl2 + Cl2 + 2H2O. (b) Decomposition of acidic KMnO4 is catalysed by sunlight: 4MnO4^- + 4H^+ $\rightarrow$ 4MnO2 + 2H2O + 3O2. (c) 3K2MnO4 + 2H2O $\rightarrow$ 2KMnO4 (purple) + MnO2 (dark brown) + 4KOH. (d) KMnO4 also acts as an oxidizing agent in alkaline medium: MnO4^- + 2H2O + 3e^- $\rightarrow$ MnO2 + 4OH^-; E° = +1.23 volt